The following discussion is intended to introduce the field of the invention to the reader. Citation of references in this section should not be construed as an admission of prior invention.
The telomerase ribonucleoprotein complex is a specialized polymerase that maintains telomeres, the specialized structures at the ends of eukaryotic chromosomes. The length and integrity of telomeres in a cell is correlated with entry of the cell into a senescent stage (i.e., loss of proliferative capacity), or alternatively, the ability of a cell to escape senescence. Of particular interest is the correlation observed between telomerase activity in human and other mammalian cells and the development of a neoplastic phenotype. For example, telomerase activity is detected in immortal cell lines and a diverse set of tumor tissues, but is not detected (ie., was absent or below the assay threshold) in normal somatic cell cultures or normal tissues adjacent to a tumor (see, U.S. Pat. Nos. 5,629,154; 5,489,508; 5,648,215; and 5,639,613; also see, Morin, 1989, Cell 59:521; Shay and Bacchetti, 1997, Eur. J. Cancer 33:787; Kim et al., 1994, Science 266:2011; Counter et al., 1992, EMBO J. 11:1921; Counter et al., 1994, Proc. Natl. Acad. Sci. U.S.A. 91, 2900; Counter et al., 1994, J. Virol. 68:3410). Moreover, a correlation between the level of telomerase activity in a tumor and the likely clinical outcome of the patient has been reported (e.g., U.S. Pat. No. 5,639,613; Langford et al., 1997, Hum. Pathol. 28:416).
Thus, telomerase plays an important role in the control of cell proliferation and in tumorigenesis. For these and other reasons, human telomerase is an ideal target for preventing and treating human diseases relating to cellular proliferation and senescence, such as cancer. The present invention provides immunological methods for preventing and treating these and other diseases in humans and nonhuman animals.